When HNO2 is dissolved in water it partially dissociates according to the equation HNO2 (RIGHT HERE SHOULD BE AN EQUILIBRIUM ARROW WITH THE TOP ARROW FACING TO THE LEFT AND THE BOTTOM ARROW FACING TOWARD THE RIGHT) H- + NO2-. A solution is prepared that contains 7.050 g of HNO2 in 1.000 kg of water. Its freezing point is 20.2929 °C. Calculate the fraction of HNO2 that has dissociated.